I saw a TV program where someone welded eight steel tubes together and used them to launch homemade ordinance. Can a spring activated tube be used to launch some of your wonderful ideas? I like the idea of keeping people far enough away so that throwing boiling water is not an option.
One of the first anti tank weapons was spring loaded . Quite dangerous to the user and hard to load . A team of Brits or Canadians used one to stop a SS Panzer group that was on the way to defend aginst the D Day invasion in WW II . The divise was designed by the Brits and part of thier issued kit .